1. Field of the Invention
The invention relates generally to semiconductor devices, and more particularly to a semiconductor chip shape alteration.
2. Description of the Related Art
The shape of a semiconductor chip is important to semiconductor technology. The shape of a semiconductor chip can cause physical stress on the semiconductor chip. Stress on the semiconductor chip causes delamination, which is the fracture of a semiconductor chip's Back End of the Line (“BEOL”) materials, which in turn leads to semiconductor chip failure. Prior art semiconductor chips are limited to square and rectangular shapes, which introduce the most stress on the semiconductor chip, because of the ninety degree corners inherent in such shapes.
FIGS. 1a-1b depict a prior art semiconductor wafer 100 and chip 110. Note the perpendicular dicing channels 102 in the prior art semiconductor wafer 100. Once diced, singulated die, also known as semiconductor chips, are separated from the semiconductor wafer 100. Once separated, the semiconductor chips 110 have a square or rectangular shape. FIG. 1b highlights the problem associated with prior art semiconductor chips 110. More specifically, a semiconductor chip 110 diced from the prior art semiconductor wafer 100 results in a square or rectangular semiconductor chip 110.
Prior art square and rectangular semiconductor chip 110 shapes introduce stress on the semiconductor chip 110, and particularly at the corners 108. Such stress causes delamination, which is a problem in prior art semiconductor chips 110. Often delamination begins in the triangular zone 106 and travels toward the active area 112 of the semiconductor chip 110. Once delamination reaches the active area 112, the semiconductor chip 110 fails. While prior art semiconductor chips 110 include a crackstop, which functions to prevent delamination into the active area 112, crackstops 112 are largely ineffective as semiconductor technology evolves because low-k dielectric is more frequently used. Low k dielectric material is particularly susceptible to delamination.
What is needed in the art is an improved semiconductor chip shape that reduces delamination.